What does the red knob do ? HID Light Term

[Navigator_Victory]

Looks like it says HID Light Term and also the other one A.C. TAP wondering what their purpose is in life they are on the back of the alternator was going to attach a pic but, it is not giving me the option....will try again later unless someone just knows what they are by my description

 

[Navigator_Victory]

Re: What does the red knob do ? HID Light Term

 

[Maclin]

Re: What does the red knob do ? HID Light Term

It is not really a knob, it is a cap that keeps the terminal underneath insulated when not used. It is for HID lights, whatever those are. I think I know but will not comment specifically on those. Evidently they can pull a different electrical load and modern automotive alternators have a tap for that circuit.

Ths A.C. tap produce alternating current straight from the alternators output with no rectifying or regulating to D.C. (direct current, as in 12vdc).

Is this a Marine alternator?

 

[Don S]

Re: What does the red knob do ? HID Light Term

It's IND. not HID. It's for a dash light that tells you your alternator isn't charging. Used in automotive, not in boats.
On carbed engines, the AC Tap is used to control automatic choke on the carb. It's an alternating current but works fine for a choke coil.

If OEM, it's marine, and what Volvo uses. Just automotive alternators with suitable shielding to meet marine specs.